Ink set, ink-jet recording method, and recorded material

ABSTRACT

An ink set includes a metallic ink composition containing a metal pigment and at least one curable ink composition selected from the group consisting of a chromatic ink composition, a black ink composition, and a white ink composition.

BACKGROUND

1. Technical Field

The present invention relates to ink sets, ink-jet recording methods,and recorded materials, and particularly to an ink set and an ink-jetrecording method that allow formation of a coating with a metallicfinish and a recorded material having such a coating.

2. Related Art

A coating with a metallic finish on a printed material is formed using,for example, a printing ink containing a gold powder formed of brassmicroparticles or a silver powder formed of aluminum microparticles as apigment, or by foil stamping or thermal transfer using metal foil.

A coating formed using a printing ink containing a gold or silverpowder, however, has a matt metallic finish and cannot attain a mirrorfinish because the metal powder used has a large average particle size,namely, 10 to 30 μm. In foil stamping or thermal transfer using metalfoil, a smooth metal foil is laminated on an adhesive-coated recordingmedium and is pressed and thermally fused by heating. This methodprovides a relatively good finish, although its application is limitedto recording media resistant to heat and deformation because the methodinvolves many production steps and the media are exposed to pressure andheat during the production steps.

There have recently been many applications of ink jetting to printing,an example of which is metallic printing. JP-A-2002-179960, for example,discloses a technique of ink-jet printing using an ink compositioncontaining a pigment formed of metal-coated plastic spherical particles.To attain a highly metallic finish, however, the spherical particlesmust be deformed to a flat shape to provide a smooth surface. Accordingto this technique, therefore, roller pressing and heating must besimultaneously performed. This requires a complicated apparatus orproduction process and also limits the range of recording media that canbe used.

JP-A-2003-292836 and JP-A-2003-306625 disclose techniques using an inkcomposition in which a colloid of a noble metal such as gold or silveris dispersed. This ink composition, however, cannot attain a metallicfinish because the noble metal colloid shows a color originating fromplasmon absorption if its particle size is reduced to several to tens ofnanometers to ensure sufficient dispersion stability. In this case, agood metallic finish can be attained by drying and heating the coatingto fuse the colloid particles. Even though a metallic finish is attainedusing these techniques, it is difficult to form a highly metallic mirrorfinish with relative specular glossinesses exceeding 200, 200, and 100at incident angles of 20°, 60°, and 85°, respectively, over a surfaceevenly without irregularities. If the particle size is increased toensure a highly metallic mirror finish, the ink composition has lowdispersion stability, and the problem of aggregation and sedimentationcannot be avoided, thus showing a significantly decreased storage life.Furthermore, it is self-evident that the use of a noble metal isdisadvantageous in terms of cost; it can only be used forhigh-value-added applications because it significantly raises the costof the ink composition.

SUMMARY

An advantage of some aspects of the invention, focusing on aluminum as aless expensive metal material, is that it provides an ink set includingan ink composition having a highly metallic mirror gloss to form acoating with a metallic finish on a printed material and a curable inkcomposition that can be used to perform metallic printing with anycolor. Another advantage of the aspects of the invention is that itprovides an ink set including a binary curable ink composition that doesnot gel during storage and has superior storage stability.

As a result of intensive studies, the inventors have found that arecorded material with high relative specular glossiness, which couldnot be achieved by the related art, can be obtained using a metallicpigment dispersion containing a particular metallic pigment, an inkcomposition containing the metal pigment, and an ink-jet recordingmethod using the ink composition. Based on these findings, the inventorshave completed the invention.

An ink set according to a first aspect of the invention includes ametallic ink composition containing a metal pigment and at least onecurable ink composition selected from the group consisting of achromatic ink composition, a black ink composition, and a white inkcomposition.

An ink set according to a second aspect of the invention includes ametallic ink composition containing a metal pigment, a first curable inkcomposition containing no colorant, and at least one second curable inkcomposition containing a colorant selected from the group consisting ofa chromatic pigment, a black pigment, and a white pigment.

It is preferable that the metal pigment include flat particles having a50% average particle size R50 of 0.5 to 3 μm, based on acircle-equivalent diameter determined from the area of the flatparticles in an X-Y plane, where X is a major axis of the flat particlesin a plane and Y is a minor axis of the flat particles in the plane, andthat the flat particles satisfy the condition R50/Z>5, where Z is thethickness of the flat particles.

It is preferable that the curable ink composition at least contain acolorant, a photopolymerization initiator, and a polymerizable compound.

It is preferable that the first curable ink composition be nonaqueousand at least contain a photopolymerization initiator and a polymerizablecompound.

It is preferable that the second curable ink composition be nonaqueousand at least contain a polymerizable compound but contain nophotopolymerization initiator.

It is preferable that the photopolymerization initiator be at least onematerial selected from the group consisting of a bisacylphosphine oxide,a monoacylphosphine oxide, an α-aminoketone, and an α-hydroxyketone.

It is preferable that the polymerizable compound be at least onematerial selected from the group consisting of an N-vinyl compound,ethylene glycol monoallyl ether, and a dendritic polymer.

It is preferable that the dendritic polymer be a dendrimer and/or ahyperbranched polymer.

It is preferable that a liquid container include one of the above inksets.

It is preferable that a liquid-ejecting apparatus include the liquidcontainer.

It is preferable that an ink-jet recording method for recording byejecting droplets of an ink composition onto a recording medium includeforming an image using the ink set according to the first aspect.

It is preferable that the image formation include simultaneouslyejecting the metallic ink composition and the curable ink compositionselected from the group consisting of the chromatic ink composition, theblack ink composition, and the white ink composition to form an image ofany color.

It is also preferable that the image formation include ejecting themetallic ink composition to form an image, ejecting the chromatic inkcomposition to form an image of any color, ejecting the black inkcomposition and/or the white ink composition, and curing the imageduring or after the ejection.

It is also preferable that the image formation include ejecting themetallic ink composition to form an image, simultaneously ejecting thechromatic ink composition, the black ink composition, and the white inkcomposition, and curing the image during or after the ejection.

It is also preferable that the image formation include ejecting themetallic ink composition to form an image, drying the image, ejectingthe chromatic ink composition, the black ink composition, and the whiteink composition to form an image of any color, and curing the image.

It is preferable that the curing be performed by ultravioletirradiation.

It is preferable that an ink-jet recording method for recording byejecting droplets of an ink composition onto a recording medium includeforming an image using the ink set according to the second aspect.

It is preferable that the image formation include simultaneouslyejecting the metallic ink composition and the first curable inkcomposition and/or the second curable ink composition and curing theimage during or after the ejection, thereby forming an image of anycolor.

It is also preferable that the image formation include ejecting themetallic ink composition to form an image, ejecting the first curableink composition and/or the second curable ink composition, and curingthe image during or after the ejection, thereby forming an image of anycolor.

It is also preferable that the image formation include ejecting thefirst curable ink composition and a second curable ink compositioncontaining the white pigment to form an image, curing the image by lightirradiation, and ejecting (i) the metallic ink composition and (ii) thefirst curable ink composition and/or (iii) a second curable inkcomposition containing the chromatic pigment or the black pigment toform an image.

It is preferable that a recorded material be obtained by one of theabove ink-jet recording methods.

The ink sets according to the aspects of the invention, which includethe metallic ink compositions containing the metal pigments, and theink-jet recording methods using the ink sets allow formation of an imagewith a highly metallic finish (metallic gloss) on a recording medium. Inaddition, the chromatic ink composition, the black ink composition, andthe white ink composition can be combined to provide an ink set thatallows formation of an image that could not be formed using known inksets, that is, an image of any color with a metallic finish.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Ink Set According to FirstEmbodiment

An ink set according to this embodiment includes a metallic inkcomposition containing a metal pigment and at least one curable inkcomposition selected from the group consisting of a chromatic inkcomposition, a black ink composition, and a white ink composition. Thisink set can be used to form chromatic, black, and white images withmetallic finishes.

The metal pigment (also referred to as a metallic pigment) preferablyincludes flat particles having a 50% average particle size R50 of 0.5 to3 μm, based on a circle-equivalent diameter determined from the area ofthe flat particles in an X-Y plane, where X is a major axis of the flatparticles in a plane and Y is a minor axis of the flat particles in theplane, and satisfying the condition R50/Z>5, where Z is the thickness ofthe flat particles.

The term “flat particles” refers to substantially flat particles havinga substantially flat surface (X-Y plane) and a substantially uniformthickness (Z). Flat metal particles having a substantially flat surfaceand a substantially uniform thickness can be formed by pulverizing adeposited metal film. Hence, a major axis of the flat particles in aplane can be defined as X, a minor axis of the flat particles in theplane can be defined as Y, and the thickness of the flat particles canbe defined as Z.

The term “circle-equivalent diameter” refers to the diameter of a circlehaving the same area as the projected area of the substantially flatsurface (X-Y plane) of the flat particles of the metallic pigment. Forexample, if the flat particles of the metallic pigment have asubstantially flat polygonal surface (X-Y plane), the circle-equivalentdiameter of the flat particles of the metallic pigment is the diameterof a circle to which the projected area of the polygonal surface isconverted.

The metallic pigment preferably has a 50% average particle size R50 of0.5 to 3 μm, more preferably 0.75 to 2 μm, based on thecircle-equivalent diameter determined from the area of the flatparticles in the X-Y plane, to provide a metallic finish and high printstability.

As for the relationship between the 50% average particle size R50 andthe thickness Z, the metallic pigment preferably satisfies the conditionR50/Z>5 to provide a highly metallic finish.

The metallic pigment used is preferably aluminum or an aluminum alloy interms of cost and providing a metallic finish. If an aluminum alloy isused, it can contain any metal or nonmetal element that provides ametallic finish. Preferred examples include silver, gold, platinum,nickel, chromium, tin, zinc, indium, titanium, and copper, which can beadded as a simple substance, an alloy, or a mixture.

The metallic pigment is produced from, for example, a composite pigmentmaterial composed of a sheet-like substrate on which a delaminationresin layer and a metal or metal compound layer are sequentiallylaminated. The metal or metal compound layer is delaminated from thesheet-like substrate at the interface between the metal or metalcompound layer and the delamination resin layer and is pulverized intoflat particles. Extracted from the flat particles are those having a 50%average particle size R50 of 0.5 to 3 μm, based on a circle-equivalentdiameter determined from the area of the flat particles in an X-Y plane,where X is a major axis of the flat particles in a plane and Y is aminor axis of the flat particles in the plane, and satisfying thecondition R50/Z>5, where Z is the thickness of the flat particles.

The major axis X, the minor axis Y, and the circle-equivalent diameterof the metallic pigment (flat particles) in the plane can be measuredusing a particle image analyzer. Examples of available particle imageanalyzers include the flow particle image analyzers FPIA-2100,FPIA-3000, and FPIA-3000S, manufactured by Sysmex Corporation.

The metal or metal compound layer is preferably formed by vacuumdeposition, ion plating, or sputtering.

The metal or metal compound layer is formed to a thickness of 20 to 100nm; in this case, a pigment having an average thickness of 20 to 100 nmcan be formed. If the metal or metal compound layer has a thickness of20 nm or more, the metallic pigment delivers high performance as ametallic pigment, including high reflectance and glossiness. If themetal or metal compound layer has a thickness of 100 nm or less, themetallic pigment has low apparent specific gravity and can thereforeattain sufficient dispersion stability.

The delamination resin layer of the composite pigment material is usedas an undercoat layer for the metal or metal compound layer and also asa delamination layer for facilitating the delamination from thesheet-like substrate. Preferred examples of the resin used for thedelamination resin layer include poly(vinyl alcohol), poly(vinylbutyral), poly(ethylene glycol), poly(acrylic acid), polyacrylamide,cellulose derivatives, acrylic acid polymers, and modified nylon.

A solution of one such resin, or a solution of a mixture of two or moreof them, is applied onto a recording medium and is dried, for example,to form a layer. Additives such as a viscosity modifier can be addedafter the application.

The delamination resin layer is formed by a generally used method suchas gravure coating, roll coating, blade coating, extrusion coating, dipcoating, or spin coating. After the application and drying, the surfacemay be planarized by calendering if necessary.

The thickness of the delamination resin layer is preferably, but notlimited to, 0.5 to 50 μm, more preferably 1 to 10 μm. A layer with athickness of less than 0.5 μm is insufficient in terms of the amount ofdispersion resin, while a layer with a thickness of more than 50 μmtends to be delaminated from the pigment layer at the interfacetherebetween when the composite pigment material is rolled.

Examples of the sheet-like substrate used include, but not limited to,releasable films such as polyester films (e.g., polytetrafluoroethylene,polyethylene, polypropylene, and polyethylene terephthalate (PET)),polyamide films (e.g., 6,6-nylon and 6-nylon), polycarbonate films,triacetate films, and polyimide films. Of these, PET or its copolymer ispreferred as the sheet-like substrate.

The thickness of the sheet-like substrate is preferably, but not limitedto, 10 to 150 μm. If the thickness is 10 μm or more, it causes noproblem with, for example, handling during the process. If the thicknessis 150 μm or less, it has flexibility and causes no problem with, forexample, rolling or delamination.

The metal or metal compound layer may be covered with a protective layersuch as a silicon oxide layer or a protective resin layer.

The silicon oxide layer used may be any layer containing silicon oxideand is preferably formed using a silicon alkoxide, such as atetraalkoxysilane, or its polymer by a sol-gel process.

The silicon oxide layer may be formed by applying an alcohol solution ofthe silicon alkoxide or its polymer and heating and firing the coating.

The protective resin layer used may be any layer that does not dissolvein a dispersion medium. Examples include poly(vinyl alcohol),poly(ethylene glycol), poly(acrylic acid), polyacrylamide, and cellulosederivatives. Of these, poly(vinyl alcohol) and cellulose derivatives arepreferred.

An aqueous solution of one such resin, or an aqueous solution of amixture of two or more of them, is applied and is dried, for example, toform a layer. The solution may contain additives such as a viscositymodifier.

The silicon oxide layer or the protective resin layer may be formed bythe same coating method as used to form the delamination resin layer.

The thickness of the protective layer is preferably, but not limited to,50 to 150 nm. If the thickness is less than 50 nm, the protective layerlacks mechanical strength. If the thickness is more than 150 nm, theprotective layer has excessive strength and is therefore difficult topulverize or disperse. In addition, such a layer can be delaminated fromthe metal or metal compound layer at the interface therebetween.

A colorant layer may be disposed between the protective layer and themetal or metal compound layer.

The colorant layer is introduced to impart any color to the compositepigment material. The colorant layer used may be any layer that cancontain a colorant capable of imparting any hue or tone in addition tothe metallic finish and glossiness of the metallic pigment used in thisembodiment. The colorant used for the colorant layer may be either a dyeor a pigment, and known dyes and pigments can be used.

The term “pigment” herein used to describe the colorant layer refers toa pigment such as a natural pigment, a synthetic organic pigment, or asynthetic inorganic pigment, as defined in the field of general pigmentchemistry; it differs from a layered pigment such as the compositepigment used in this embodiment.

The colorant layer may be formed by any method, preferably, by coating.

If the colorant used for the colorant layer is a pigment, it preferablyfurther contains a colorant dispersion resin. Preferably, the pigment,the colorant dispersion resin, and optionally other additives aredispersed or dissolved in a solvent before the solution is applied toform a uniform liquid film by spin coating and is dried to form a thinresin film.

In the production of the composite pigment material, it is preferable interms of operating efficiency to form both the colorant layer and theprotective layer by coating.

The composite pigment material can be composed of a plurality of layeredstructures, each having the delamination resin layer and the metal ormetal compound layer that are sequentially laminated. In this case, thetotal thickness of the layered structures of the metal or metal compoundlayers except the sheet-like substrate and the overlying delaminationresin layer, for example, the total thickness of one metal or metalcompound layer, one delamination resin layer, and one metal or metalcompound layer, or that of one delamination resin layer and one metal ormetal compound layer, is preferably 5,000 nm or less. If the thicknessis 5,000 nm or less, the composite pigment material is not cracked ordelaminated when rolled and therefore has superior storage stability. Inaddition, a pigment formed of the composite pigment material ispreferred in terms of glossiness.

Another example is a structure in which the delamination resin layer andthe metal or metal compound layer are sequentially laminated on eachsurface of the sheet-like substrate, although the invention is notlimited to the above examples.

The delamination from the sheet-like substrate may be performed by anymethod, preferably, by dipping the composite pigment material in aliquid. It is also preferred to perform the delamination simultaneouslywith pulverization by dipping the composite pigment material in a liquidunder ultrasonic treatment.

The pigment thus formed can be used to prepare a stable dispersion onlyby dispersing it in a solvent because the delamination resin layerfunctions as a protective colloid. In addition, the resin derived fromthe delamination resin layer functions to facilitate adhesion of the inkcomposition containing the pigment to a recording medium such as paper.

The metallic ink composition used for the ink set according to thisembodiment contains the metallic pigment, an organic solvent, and aresin.

The concentration of the metallic pigment in the ink composition ispreferably 0.1% to 10.0% by weight.

If the concentration of the metallic pigment in the ink composition isequal to or more than 0.1% by weight and less than 1.5% by weight, ahalf-mirror-like finish with a glossy but see-through appearance can beprinted by ejecting an insufficient amount of ink to cover a printingsurface, while a metallic finish with high glossiness can be formed byejecting a sufficient amount of ink to cover the printing surface. Forexample, such an ink composition is suitable for forming a half-mirrorimage or a metallic finish with high glossiness on a transparentrecording medium. If the concentration of the metallic pigment in theink composition is 1.5% by weight or more, a matt metallic finish can beformed rather than a highly glossy finish because the pigment particlesare randomly arranged on the printing surface. For example, such an inkcomposition is suitable for forming a shield layer on a transparentrecording medium.

The organic solvent used is preferably a polar organic solvent. Examplesinclude alcohols (such as methyl alcohol, ethyl alcohol, propyl alcohol,butyl alcohol, isopropyl alcohol, and fluorinated alcohols), ketones(such as acetone, methyl ethyl ketone, and cyclohexanone), carboxylateesters (such as methyl acetate, ethyl acetate, propyl acetate, butylacetate, methyl propionate, and ethyl propionate), and ethers (such asdiethyl ether, dipropyl ether, tetrahydrofuran, and dioxane).

In particular, the organic solvent preferably contains one or morealkylene glycol ethers that are liquid at normal temperature andpressure.

Examples of alkylene glycol ethers include ethylene glycol ethers andpropylene glycol ethers based on alkyl groups (such as methyl, n-propyl,i-propyl, n-butyl, i-butyl, hexyl, and 2-ethylhexyl groups), allylgroups, which have a double bond, and phenyl groups. Such ethers have nocolor and little smell, behave both as an alcohol and an ether becauseof the ether and hydroxyl groups in their molecules, and are liquid atroom temperature. These ethers can be divided into monoethers, in whichone of the hydroxyl groups has been substituted, and diethers, in whichthe two hydroxyl groups have been substituted. These ethers may be usedin combination.

In particular, the organic solvent used is preferably a mixture of analkylene glycol diether, an alkylene glycol monoether, and a lactone.

Examples of alkylene glycol monoethers include ethylene glycolmonomethyl ether, ethylene glycol monoethyl ether, ethylene glycolmonoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycolmonohexyl ether, ethylene glycol monophenyl ether, diethylene glycolmonomethyl ether, diethylene glycol monoethyl ether, diethylene glycolmonobutyl ether, diethylene glycol dimethyl ether, diethylene glycoldiethyl ether, triethylene glycol monomethyl ether, triethylene glycolmonoethyl ether, triethylene glycol monobutyl ether, tetraethyleneglycol monomethyl ether, tetraethylene glycol monoethyl ether, propyleneglycol monomethyl ether, propylene glycol monoethyl ether, dipropyleneglycol monomethyl ether, and dipropylene glycol monoethyl ether.

Examples of alkylene glycol diethers include ethylene glycol dimethylether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether,diethylene glycol dimethyl ether, diethylene glycol diethyl ether,diethylene glycol dibutyl ether, triethylene glycol dimethyl ether,triethylene glycol diethyl ether, triethylene glycol dibutyl ether,tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether,tetraethylene glycol dibutyl ether, propylene glycol dimethyl ether,propylene glycol diethyl ether, dipropylene glycol dimethyl ether, anddipropylene glycol diethyl ether.

Examples of lactones include γ-butyrolactone, δ-valerolactone, andε-caprolactone.

Examples of the resin used for the metallic ink composition includeacrylic resin, styrene-acrylic resin, rosin-modified resin, terpeneresin, polyester, polyamide, epoxy resin, poly(vinyl chloride), vinylchloride-vinyl acetate copolymer, fiber-based resin (e.g., celluloseacetate butyrate and hydroxypropylcellulose), poly(vinyl butyral),polyacrylic polyol, poly(vinyl alcohol), and polyurethane.

The resin used may also be a nonaqueous emulsion of polymermicroparticles, which refers to a nonaqueous dispersion (NAD) preparedby stably dispersing microparticles of polyurethane, acrylic resin, oracrylic polyol resin, for example, in an organic solvent. Examples ofpolyurethane dispersions include Sanprene IB-501 and Sanprene IB-F370,manufactured by Sanyo Chemical Industries, Co., Ltd. Examples of acrylicpolyol resin dispersions include N-2043-60MEX and N-2043-AF-1,manufactured by Harima Chemicals, Inc.

The resin is preferably added to the ink composition in an amount of0.1% to 10% by weight to facilitate adhesion of the pigment to arecording medium.

The ink composition preferably further contains at least one materialselected from the group consisting of glycerol, poly(alkylene glycol)s,and saccharides in a total amount of 0.1% to 10% by weight.

Adding such a material can inhibit ink drying and clogging to stabilizeink ejection, thus improving the image quality of a recorded material.

Poly(alkylene glycol)s are linear polymer compounds having ether bondsrepeated in their main chains and are produced by, for example,ring-opening polymerization of cyclic ethers.

Examples of poly(alkylene glycol)s include poly(ethylene glycol),poly(propylene glycol), ethylene oxide-propylene oxide copolymer, andderivatives thereof. Any type of copolymer such as a random copolymer, ablock copolymer, a graft copolymer, or an alternating copolymer can beused.

A preferred example of a poly(alkylene glycol) is represented by thefollowing formula:

HO—(C_(n)H_(2n)O)_(m)—H

(where n is an integer of 1 to 5 and m is an integer of 1 to 100)

In the above formula, the integer n may be either a single constant or acombination of two or more constants within the above range. Forexample, if n is 3, the formula gives (C₃H₆O)_(m), and if n is acombination of 1 and 4, the formula gives (CH₂O—C₄H₈O)_(m). Also, theinteger m may be either a single constant or a combination of two ormore constants within the above range. For example, if m is acombination of 20 and 40 in the above example, the formula gives(CH₂O)₂₀—(C₄H₈O)₄₀, and if m is a combination of 10 and 30, the formulagives (CH₂O)₁₀—(C₄H₈O)₃₀. In addition, any combination of the integers nand m may be selected within the above ranges.

Examples of saccharides include monosaccharides such as pentoses,hexoses, heptoses, and octoses and polysaccharides such asdisaccharides, trisaccharides, and tetrasaccharides, and derivativesthereof can also be used, including reduced derivatives such as sugaralcohols and deoxy sugars, oxidized derivatives such as aldonic acidsand uronic acids, dehydrated derivatives such as glycoseens, aminosugars, and thio sugars. The term “polysaccharides” refers to sugars ina broad sense, including naturally occurring substances such as alginicacid, dextrin, and cellulose.

The metallic ink composition preferably further contains at least oneacetylene glycol surfactant and/or at least one silicone surfactant inan amount of 0.01% to 10% by weight of the content of the pigment in theink composition.

Adding such a surfactant can improve the wettability of the metallic inkcomposition on a recording medium, thus providing quick adhesion.

Preferred examples of acetylene glycol surfactants include Surfynol® 465and Surfynol® 104 (trade names, manufactured by Air Products andChemicals, Inc.) and Olfine® STG and Olfine® E1010 (trade names,manufactured by Nissin Chemical Industry Co., Ltd.).

The silicone surfactant used is preferably polyester-modified siliconeor polyether-modified silicone, as exemplified by BYK-347, BYK-348,BYK-UV3500, BYK-UV3510, BYK-UV3530, and BYK-UV3570 (manufactured byBYK-Chemie Japan K.K.).

The metallic ink composition can be prepared by a commonly used method.For example, the pigment ink composition can be prepared by mixing themetallic pigment, a dispersant, and the solvent, preparing a pigmentdispersion with desired ink properties using a ball mill, a bead mill,or a jet mill or with ultrasonic treatment, and adding a binder resin,the solvent, and other additives (such as a dispersion aid and aviscosity modifier) with stirring.

As another example, the composite pigment material may be subjected to aultrasonic treatment in a solvent to form a composite pigment dispersionbefore the dispersion is mixed with the necessary ink solvent.Alternatively, the composite pigment material may be subjected to theultrasonic treatment directly in the ink solvent to form the inkcomposition.

Although the physical properties of the metallic ink composition are notparticularly limited, it preferably has, for example, a surface tensionof 20 to 50 mN/m. If the surface tension is less than 20 mN/m, it can bedifficult to eject ink droplets because the ink composition widely wetsthe surface of or exudes from a head of an ink-jet recording printer. Ifthe surface tension is more than 50 mN/m, it can be difficult to performexcellent printing because the ink composition does not wet the surfaceof a recording medium.

Next, the curable ink composition used for the ink set according to thisembodiment will be described. The ink set according to this embodimentincludes at least one curable ink composition selected from the groupconsisting of a chromatic ink composition, a black ink composition, anda white ink composition.

The chromatic ink composition is an ink composition containing achromatic pigment. The term “chromatic” refers to any color other thancolors on a grayscale from black to white (achromatic colors). Thechromatic pigment used is preferably an organic pigment in terms ofstorage stability, for example, light resistance, weather resistance,and gas resistance.

Examples of the chromatic pigment used include azo pigments (e.g.,insoluble azo pigments, condensed azo pigments, azo lakes, and chelateazo pigments), polycyclic pigments (e.g., phthalocyanine pigments,perylene and perinone pigments, anthraquinone pigments, quinacridonepigments, dioxane pigments, thioindigo pigments, isoindolinone pigments,and quinophthalone pigments), chelate dyes (e.g., basic chelate dyes andacidic chelate dyes), dye lakes (e.g., basic dye lakes and acidic dyelakes), nitro pigments, nitroso pigments, aniline black, and daylightfluorescent pigments. These pigments can be used alone or in combinationof two or more of them.

Specific examples include C.I. Pigment Yellow 1 (Fast Yellow G), 2, 3,12 (Disazo Yellow AAA), 13, 14, 16, 17, 24, 34, 35, 37, 42 (yellow ironoxide), 53, 55, 73, 74, 75, 81, 83 (Disazo Yellow HR), 93, 94, 95, 97,98, 100, 101, 104, 108, 109, 110, 117, 120, 128, 129, 138, 139, 150,153, 154, 155, 180, 185, and 213; C.I. Pigment Red 1, 2, 3, 5, 7, 17, 22(Brilliant Fast Scarlet), 23, 31, 38, 48:2 (Permanent Red 2B (Ba)), 48:2(Permanent Red 2B (Ca)), 48:3 (Permanent Red 2B (Sr)), 48:4 (PermanentRed 2B (Mn)), 49:1, 52:2, 53:1, 57:1 (Brilliant Carmine 6B), 60:1, 63:1,63:2, 64:1, 81 (Rhodamine 6G Lake), 83, 88, 101 (red iron oxide), 104,105, 106, 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168,170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 209, and 219; C.I.Pigment Violet 19; C.I. Pigment Blue 1, 2, 15 (Phthalocyanine Blue R),15:1, 15:2, 15:3 (Phthalocyanine Blue G), 15:4, 15:6 (PhthalocyanineBlue E), 16, 17:1, 22, 56, 60, and 63; C.I. Pigment Green 1, 4, 7, 8,10, 17, 18, and 36.

Any other pigment that is not listed in the color index can be used aslong as the pigment is insoluble to water.

The black ink composition is an ink composition containing a blackpigment. Examples of the black pigment used include carbon black (C.I.Pigment Black 7) such as furnace black, lamp black, acetylene black, andchannel black; metal pigments such as copper oxide and iron oxide (C.I.Pigment Black 11); and organic pigments such as aniline black (C.I.Pigment Black 1). Of these, carbon black is preferred for ink-jet usebecause it has relatively low specific gravity and does not easilysediment in water. These pigments may be used alone or as a mixture oftwo or more of them.

The white ink composition is an ink composition containing a whitepigment. An example of the white pigment is an oxide of a Group IVelement, such as titanium dioxide or zirconium dioxide. Other examplesinclude calcium carbonate, calcium sulfate, zinc oxide, barium sulfate,barium carbonate, silica, alumina, kaolin, clay, talc, white clay,aluminum hydroxide, magnesium carbonate, and white hollow resinemulsions. Preferably, these white pigments are used alone or as amixture of two or more of them.

White hollow resin emulsions are oil-based dispersions containing hollowpolymer microparticles.

The white pigment preferably has a primary particle size of 1 μm or lessin terms of whiteness.

The term “primary particle size” refers to the size of a particleconstituted of single crystals or crystallites equivalent thereto. Theprimary particle size of the pigment is measured by electron microscopy,where the size of the pigment particles is measured on an electronmicrograph. A more reliable measurement can be obtained by dispersingthe pigment in an organic solvent, immobilizing the pigment on a supportfilm, and measuring the primary particle size on a transmission electronmicrograph after image processing. For example, the primary particlesize is determined by measuring the major and minor axes of the primaryparticles, calculating the diameters of circles having the same areas asthe primary particles as the primary particle sizes, and averaging theprimary particle sizes of at least 50 particles randomly selected from apredetermined field of view. While any other method with equivalentreliability may be employed, a measurement obtained by the methoddescribed above should be used if there is any substantial difference inmeasurement.

The contents of the pigments in the chromatic ink composition and theblack ink composition are each preferably 0.1% to 30% by weight, morepreferably 0.5% to 12% by weight, although they may be determined caseby case. The content of the pigment in the white ink composition ispreferably 1.0% by weight or more, more preferably 5.0% by weight ormore, still more preferably 10% to 20% by weight, in terms of whiteness.

In terms of color density, the contents of the pigments in the chromaticink composition, the black ink composition, and the white inkcomposition are each preferably 0.1% by weight or more, more preferably1.0% by weight or more, still more preferably 3.0% to 10.0% by weight.

In addition to the pigment used as a colorant, the curable inkcomposition used for the ink set according to this embodiment preferablycontains a dispersant for dispersing the pigment. The dispersant usedmay be any dispersant that can be used for this type of pigment ink, forexample, a cationic dispersant, an anionic dispersant, a nonionicdispersant, or a surfactant.

Examples of the anionic dispersant include poly(acrylic acid),poly(methacrylic acid), acrylic acid-acrylonitrile copolymer, vinylacetate-acrylate copolymer, acrylic acid-alkyl acrylate copolymer,styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer,styrene-acrylic acid-alkyl acrylate copolymer, styrene-methacrylicacid-alkyl acrylate copolymer, styrene-α-methylstyrene-acrylic acidcopolymer, styrene-α-methylstyrene-acrylic acid-alkyl acrylatecopolymer, styrene-maleic acid copolymer, vinylnaphthalene-maleic acidcopolymer, vinyl acetate-ethylene copolymer, vinyl acetate-vinylethylenecarbonate copolymer, vinyl acetate-maleate copolymer, vinylacetate-crotonic acid copolymer, and vinyl acetate-acrylic acidcopolymer.

Examples of the nonionic dispersant include polyvinylpyrrolidone,poly(propylene glycol), and vinylpyrrolidone-vinyl acetate copolymer.

Examples of the surfactant used as a dispersant include anionicsurfactants such as sodium dodecylbenzenesulfonate, sodium laurate, andammonium salts of polyoxyethylene alkyl ether sulfate; and nonionicsurfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylesters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylenealkylphenyl ethers, polyoxyethylene alkylamines, and polyoxyethylenealkylamides. In particular, styrene-(meth)acrylic acid copolymer ispreferred to enhance the dispersion stability of the pigment.

Other examples of dispersants include polyoxyalkylene polyalkyleneamines and sorbitan esters. Examples of polyoxyalkylene polyalkylenepolyamines, as represented by the formula(C₂H₄N)_(n)—(PO)_(x)-(EO)_(y)—OH (where n, x, and y are integers of 1 ormore; PO is propylene oxide; and EO is ethylene oxide), include DiscoleN-503, N-506, N-509, N-512, N-515, N-518, and N-520.

In addition to the colorant described above, the photocurable inkcomposition used for the ink set according to this embodiment preferablycontains a photopolymerization initiator and a polymerizable compound.

The photopolymerization initiator used is preferably at least onematerial selected from the group consisting of a bisacylphosphine oxide,a monoacylphosphine oxide, an α-aminoketone, and an α-hydroxyketone.

The bisacylphosphine oxide, the monoacylphosphine oxide, theα-aminoketone, and the α-hydroxyketone can absorb light with wavelengthsof 365 nm or more. Hence, at least one of these compounds can be used asthe photopolymerization initiator to provide a more transparent curableink composition suitable for ultraviolet light with wavelengths of 395nm or more. In particular, the bisacylphosphine oxide and themonoacylphosphine oxide show absorption at longer wavelengths than theα-aminoketone and the α-hydroxyketone.

An example of the bisacylphosphine oxide isbis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, as is available underthe trade name of Irgacure 819 (manufactured by Ciba Specialty ChemicalsInc.).

An example of the monoacylphosphine oxide is2,4,6-trimethylbenzoyldiphenylphosphine oxide, as is available under thetrade name of Darocur TPO (manufactured by Ciba Specialty ChemicalsInc.).

An example of the α-aminoketone is2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1, as isavailable under the trade name of Irgacure 369 (manufactured by CibaSpecialty Chemicals Inc.).

Examples of the α-hydroxyketone include2-hydroxy-2-methyl-1-phenylpropan-1-one and 1-hydroxycyclohexyl phenylketone, as are available under the trade names of Darocur 1173 andIrgacure 184 and 127 (manufactured by Ciba Specialty Chemicals Inc.).

The photocurable ink composition used for the ink set according to thisembodiment may contain two or more such photopolymerization initiatorsas described above, which may be used in combination with otherphotopolymerization initiators.

Typical examples of photopolymerization initiators that can be used incombination include benzoin methyl ether, benzoin ethyl ether, isopropylbenzoin ether, isobutyl benzoin ether, 1-phenyl-1,2-propandione2-(o-ethoxycarbonyl)oxime, benzil, diethoxyacetophenone, benzophenone,chlorothioxanthone, 2-chlorothioxanthone, isopropylthioxanthone,diethylthioxanthone, 2-methylthioxanthone, polychlorinated polyphenyl,and hexachlorobenzene. Of these, isobutyl benzoin ether and1-phenyl-1,2-propandione 2-(o-ethoxycarbonyl)oxime are preferred.

Other examples include photopolymerization initiators available underthe trade names of Vicure 10 and 30 (manufactured by Stauffer ChemicalCompany); Irgacure 127, 184, 500, 651, 2959, 907, 369, 379, 754, 1700,1800, 1850, 819, 4265, and OXE01 and Darocur 1173, ITX, and TPO(manufactured by Ciba Specialty Chemicals Inc.); Quantacure CTX and ITX(manufactured by Aceto Corporation); Kayacure DETX-S (manufactured byNippon Kayaku Co., Ltd.); ESACURE KIP150 (manufactured by Lamberti Spa);and Lucirin TPO (manufactured by BASF SE).

The polymerizable compound used is preferably at least one materialselected from the group consisting of an N-vinyl compound, ethyleneglycol monoallyl ether, and a dendritic polymer in terms of storagestability.

Examples of the polymerizable compound include allylic compounds,preferably, allyl ether compounds such as ethylene glycol monoallylether, trimethylolpropane diallyl ether, trimethylolpropane monoallylether, glycerol monoallyl ether, allyl glycidyl ether, andpentaerythritol triallyl ether. In particular, ethylene glycol monoallylether, trimethylolpropane diallyl ether, and N-vinyl compounds arepreferred.

Ethylene glycol monoallyl ether and N-vinyl compounds, which aremonofunctional radical polymerizable monomers, are preferred becausethey have a low tendency to undergo undesirable polymerization due todark reaction during storage. In particular, allylic compounds such asethylene glycol monoallyl ether and trimethylolpropane diallyl ether donot polymerize alone even in the presence of carbon radicals produced bydecomposition of the radical photopolymerization initiator.

The N-vinyl compound used is preferably N-vinylformamide in terms ofcurability.

The amount of ethylene glycol monoallyl ether or N-vinyl compound addedis preferably 50% to 95% by weight.

The dendritic polymer used is preferably a hyperbranched polymer and/ora dendrimer in terms of reducing ink viscosity.

The term “hyperbranched polymer” refers to a dendritic polybranchedpolymer that includes many branches but does not necessarily have aregular molecular structure. The hyperbranched polymer used ispreferably one having a dipentaerythritol core with branches offunctional groups, as is available under the trade names of STAR-501 andSTAR-502 (manufactured by Osaka Organic Chemical Industry Ltd.).

In this embodiment, Viscoat #1000 (manufactured by Osaka OrganicChemical Industry Ltd.) and STAR-501 are used as hyperbranched polymers.Viscoat #1000 and STAR-501 are hyperbranched polymers having adipentaerythritol core with branches of functional groups. Viscoat #1000contains ethylene glycol diacrylate as a diluent monomer and has aviscosity of 273 Pa·s and 14 functional groups (acrylic groups).STAR-501 contains dipentaerythritol hexaacrylate as a diluent monomerand has a viscosity of 210 Pa·s and 20 to 99 functional groups (acrylicgroups). Both are preferred because they have acryloyl groups on theiroutermost sides.

While dendrimers are costly to produce because they have highstereoregularity and therefore require numerous production steps,hyperbranched polymers are advantageous in terms of cost because theyhave lower stereoregularity and can therefore be relatively easilysynthesized.

The term “dendrimer” refers to a dendritic polybranched polymer thatincludes many branches and has a regular, flawless molecular structure.This type of polymer allows reactive functional groups to be arranged onthe outermost side of a molecule at a higher density in a moreconcentrated manner than commonly used linear polymers.

The amount of dendritic polymer added is preferably 1.0% to 30.0% byweight.

The curable ink composition may contain any other polymerizablecompounds that can be polymerized with radicals or ions produced fromthe photopolymerization initiator. Such polymerizable compounds arethose whose molecules can serve as structural units of a basic polymerstructure. These polymerizable compounds are also referred to asphotopolymerizable monomers, including monofunctional monomers,bifunctional monomers, and polyfunctional monomers.

Typical examples of the monofunctional monomers include(2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate,(2-methyl-2-isobutyl-1,3-dioxolan-4-yl)methyl acrylate, phenoxyethylacrylate, isobornyl acrylate, methoxydiethylene glycol monoacrylate,acryloylmorpholine, lauryl methacrylate, allyl glycol, 2-hydroxyethylmethacrylate, cyclohexyl methacrylate, and oxetane methacrylate.

Typical examples of the bifunctional monomers include ethylene glycoldimethacrylate, diethylene glycol diacrylate, diethylene glycoldimethacrylate, tripropylene glycol diacrylate, 1,9-nonandioldiacrylate, polyethylene glycol diacrylate, tetraethylene glycoldimethacrylate, 1,6-hexandiol diacrylate, 1,6-hexandiol dimethacrylate,neopentyl glycol diacrylate, neopentyl glycol dimethacrylate,2-hydroxy-1,3-dimethacryloxypropane, and neopentyl glycolhydroxypivalate diacrylate.

Typical examples of the polyfunctional monomers includetrimethylolpropane triacrylate, trimethylolpropane trimethacrylate, anethylene oxide adduct of trimethylolpropane triacrylate, a propyleneoxide adduct of trimethylolpropane triacrylate, an ethylene oxide adductof glycerol triacrylate, ethylene oxide-modified glycerol triacrylate, apropylene oxide adduct of glycerol triacrylate, pentaerythritoltriacrylate, dipentaerythritol hexaacrylate,(2,2,2-triacryloyloxymethyl)ethyl hydrogen phthalate, dipentaerythritolpolyacrylate, trimethylolpropane diallyl ether, pentaerythritol triallylether, and glycerol monoallyl ether.

The photocurable ink composition may contain a polymerizationaccelerator, for example, microparticles having polymerizable functionalgroups.

The polymerization accelerator used is preferably, but not limited to,at least one of an amine compound, a thioxanthone, or polymerizablemicroparticles. Examples include aminobenzoates such as Darocur EHA andEDB (manufactured by Ciba Specialty Chemicals Inc.), thioxanthone,isopropylthioxanthone, dimethylthioxanthone, diethylthioxanthone, andpolymerizable microparticles having polymerizable functional groups ontheir surfaces.

The polymerization acceleration mechanism of the microparticles havingpolymerizable functional groups has not been clearly understood. It isassumed that radicals produced by decomposition of thephotopolymerization initiator after ultraviolet absorption are trappedand stabilized on the surfaces of the microparticles to triggerpolymerization reaction of the polymerizable functional groupsintroduced on the surfaces of the microparticles and the polymerizablecompound adsorbed thereon, thus accelerating the polymerizationreaction.

The microparticles having the polymerizable functional groups may be,but not limited to, an extender pigment, for example, an inorganiccompound such as silica, alumina, titania, or calcium oxide. Of these,transparent compounds such as silica and alumina are preferable, andsilica is particularly preferable.

Examples of the polymerizable functional groups of the microparticlesinclude, but not limited to, acryloyl groups and methacryloyl groups.Polymerizable functional groups having one or more double bonds are alsopermitted.

The size of the microparticles is preferably, but not limited to, 10 to200 nm.

Although the method used to prepare the microparticles having thepolymerizable functional groups is not particularly limited, they can beprepared by, for example, forming silica microparticles having manyhydroxyl groups by a sol-gel process using a silane compound such astetraethoxysilane and allowing the microparticles to react with acompound (silane coupling agent) capable of adding polymerizablefunctional groups to the hydroxyl groups.

The content of the microparticles having the polymerizable functionalgroups is not particularly limited and may be determined according to,for example, the usage form and conditions and the relationship betweenthe viscosity and polymerizability of the ink composition. The contentis preferably 10% or less of the total weight of the ink composition.

The amount of polymerization accelerator added is preferably 0.01% to5.0% by weight.

The curable ink composition may contain at least one thermal radicalpolymerization inhibitor to achieve higher storage stability.

The thermal radical polymerization inhibitor used is preferably ahindered phenolic compound or a hindered amine light stabilizer (HALS).An example of the hindered phenolic compound is Irgastab UV-22(manufactured by Ciba Specialty Chemicals Inc.). An example of the HALSis Irgastab UV-10 (manufactured by Ciba Specialty Chemicals Inc.).

The curable ink composition may contain a sensitizer.

The sensitizer used may be a coumarin compound or a thioxanthonecompound.

The sensitizer is a compound that allows radicals to be produced byhydrogen extraction, energy transfer, or electron transfer when thecompound is excited by absorption of light with which the inkcomposition is irradiated for photocuring.

Coumarin compounds not only provide a sensitization effect bytransferring energy to other molecules when they are excited byultraviolet absorption, but also emit fluorescence when they fall totheir ground states. It is assumed that the photopolymerizationinitiator absorbs the fluorescence resulting from the light irradiationto attain increased sensitivity. The ink set according to thisembodiment is particularly effective for a printed material with a thickfilm. While less irradiation light reaches deep inside the thick film onthe printed material, a coumarin compound, having the above effect,emits fluorescence inside the ink to improve sensitivity, thussuccessfully curing the inside of the film on the printed material.

Preferred examples of coumarin compounds include coumarin,4-methylcoumarin, 7-hydroxycoumarin, 7-amino-4-methylcoumarin,7-hydroxy-4-trifluoromethylcoumarin,3-(2-benzothiazoyl)-7-(diethylamino)coumarin,7-acetoxy-3-(2-benzoxazoyl)coumarin,6,7-diethoxy-4-(trifluoromethyl)coumarin, and2,3,6,7-tetrahydro-9-methyl-1H,5H-quinolizino(9,1-gh)coumarin.

Preferred examples of thioxanthone compounds include thioxanthone,isopropylthioxanthone, 2,4-diethylthioxanthone, and chlorothioxanthone.

The concentration of the sensitizer in the curable ink composition ispreferably 0.01% to 1.0% by weight.

The curable ink composition can be prepared by a commonly used method.For example, a desired curable ink composition can be prepared by mixinga pigment dispersion and an ink solvent and filtering the mixture.

Liquid Container and Liquid-Ejecting Apparatus

According to this embodiment, a liquid container including the ink setdescribed above can be provided. According to this embodiment,additionally, a liquid-ejecting apparatus including the liquid containercan be provided.

Ink-Jet Recording Method

An ink-jet recording method according to this embodiment for recordingby driving an ink-jet head to eject droplets of an ink composition ontoa recording medium includes forming an image using the ink set describedabove.

The metallic ink composition containing the metal pigment can be usedalone to form an image with a metallic finish whose relative specularglossinesses at incident angles of 20°, 60°, and 85°, as specified inJapanese Industrial Standards (JIS) 28741, are measured to be 200 ormore, 200 or more, and 100 or more, respectively, at the same time. Theuse of this metallic ink composition allows formation of images withdesired metallic finishes, ranging from matt images to glossy images.

Specifically, an image with a matt metallic finish can be formed if therelative specular glossinesses at incident angles of 20°, 60°, and 85°,as specified in JIS Z8741, are measured to be equal to or more than 200and less than 400, equal to or more than 200 and less than 400, and 100or more, respectively, at the same time.

In addition, a glossy metallic image on which a reflection of an objectcan be slightly seen can be formed if the relative specular glossinessesat incident angles of 20°, 60°, and 85°, as specified in JIS 28741, aremeasured to be equal to or more than 400 and less than 600, equal to ormore than 400 and less than 600, and 100 or more, respectively, at thesame time.

Furthermore, a sharp, glossy metallic image on which a reflection of anobject can be clearly seen, namely, a mirror-finished image, can beformed if the relative specular glossinesses at incident angles of 20°,60°, and 85°, as specified in JIS 28741, are measured to be 600 or more,600 or more, and 100 or more, respectively, at the same time.

An image can be formed by simultaneously ejecting the metallic inkcomposition containing the metal pigment and at least one curable inkcomposition selected from the group consisting of the chromatic inkcomposition, the black ink composition, and the white ink composition.This allows a metallic appearance to be added to the colors of thechromatic pigment, the black pigment, and the white pigment.

If the metallic ink composition containing the metal pigment and thecurable ink compositions such as the chromatic ink composition, theblack ink composition, and the white ink composition are separatelyejected, for example, it is preferable to form an image with a metallicfinish using the metallic ink composition containing the metal pigmentbefore the image formation using the chromatic ink composition.

The metallic pigment does not easily permeate an ink-accepting layer ona recording medium and therefore remains deposited on the recordingmedium whether it has the ink-accepting layer or not. In contrast, whenthe chromatic ink composition is ejected onto the ink-accepting layer onthe recording medium, the pigment contained therein easily permeates theink-accepting layer. Hence, the color of the pigment of the chromaticink composition can be made more distinct if the metallic inkcomposition containing the metal pigment is ejected onto the recordingmedium to form a deposited layer of the metallic pigment before thepigment of the chromatic ink composition is deposited thereon.

It is also possible to form an image by ejecting the metallic inkcomposition to form an image with a metallic finish, ejecting thechromatic ink composition to form an image of any color with a metallicfinish, and ejecting the black ink composition and/or the white inkcomposition.

Examples of the method for ejecting the ink compositions will bedescribed below.

A first method is electrostatic attraction. For example, ink dropletsare continuously ejected from a nozzle by applying a strong electricfield across acceleration electrodes disposed on and in front of thenozzle. The ink droplets then travel between deflection electrodes towhich print information signals are supplied, thereby performingrecording. Alternatively, the ink droplets are ejected based on theprint information signals without being deflected.

A second method is to forcedly eject ink droplets by mechanicallyoscillating a nozzle with a quartz oscillator, for example, whileapplying pressure to the ink with a small pump. The ejected inkdroplets, electrically charged at the same time as the ejection, travelbetween deflection electrodes to which print information signals aresupplied, thereby performing recording.

A third method is the use of a piezoelectric element. Ink droplets areejected by simultaneously supplying pressure and print informationsignals to the ink through the piezoelectric element, thereby performingrecording.

A fourth method is the use of thermal energy to suddenly expand the ink.Ink droplets are ejected by heating the ink with minute electrodes basedon print information signals to cause the ink to form bubbles, therebyperforming recording.

Any of the methods described above can be used for the ink-jet recordingmethod according to this embodiment, and the ink set according to thisembodiment can be used with an ink-jet cartridge based on any of theabove methods.

After the ejection of the curable ink compositions, droplets depositedon the recording medium are cured and/or dried by a common method.

An example of the method for curing includes ejecting the metallic inkcomposition to form an image, ejecting the chromatic ink composition,and curing the image during or after the ejection. Another exampleincludes ejecting the metallic ink composition to form an image,simultaneously ejecting the chromatic ink composition, the black inkcomposition, and the white ink composition, and curing the image duringor after the ejection. A further example includes ejecting the metallicink composition to form an image, ejecting the chromatic ink compositionto form an image of any color, ejecting the black ink composition and/orthe white ink composition, and curing the image during or after theejection.

These methods allow formation of a full-color image with a metallicfinish.

The drying and the curing can also be combined by, for example, ejectingthe metallic ink composition to form an image, drying the image,ejecting the chromatic ink composition, the black ink composition, andthe white ink composition to form an image of any color, and curing theimage.

This method allows formation of a full-color image with a metallicfinish.

The curing is preferably performed by ultraviolet irradiation. It ispreferable to select appropriate conditions for ultraviolet irradiationbased on the amount and thickness of the ink compositions deposited on,for example, a substrate or a recording medium. Although it may bedifficult to exactly specify such conditions, the wavelength of lightemitted from a light irradiation apparatus, for example, is preferably350 to 450 nm.

The dosage of ultraviolet radiation is preferably 10 to 10,000 mJ/cm²,more preferably 50 to 6,000 mJ/cm². Within such ranges of ultravioletdosage, the curable ink compositions can be sufficiently cured.

The ultraviolet irradiation may be performed using, for example, a lampsuch as a metal halide lamp, a xenon lamp, a carbon arc lamp, a chemicallamp, a low-pressure mercury lamp, or a high-pressure mercury lamp. Forexample, commercially available lamps such as H-lamps, D-lamps, andV-lamps manufactured by Fusion UV Systems, Inc. can be used.

To reduce energy consumption, particularly, the ultraviolet irradiationis preferably performed using an ultraviolet light-emittingsemiconductor device such as an ultraviolet light-emitting diode(ultraviolet LED) or an ultraviolet light-emitting semiconductor laser.

The recording medium used is not particularly limited, and variousrecording media can be used, including plain paper, ink-jet paper (mattpaper and glossy paper), glass, plastic, film, metal, and printedcircuit boards.

If the recording medium has an ink-accepting layer, nonheating printingis preferred to avoid heat damage.

If the recording medium has no ink-accepting layer, heating printing ispreferred to increase drying speed and to attain high glossiness.

Examples of the method for heating include heating the recording mediumby bringing it into contact with a heat source and noncontact heatingusing infrared light, microwaves (electromagnetic waves with peakwavelengths around 2,450 MHz), or hot air.

The heating is preferably performed before, during, and/or after theprinting; in other words, the recording medium may be heated at any timebefore, during, or after the printing, or throughout the printing. Theheating temperature is preferably 30° C. to 80° C., more preferably 40°C. to 60° C., depending on the type of recording medium used.

Recorded Material

A recorded material according to this embodiment is obtained byrecording using the ink set and the ink-jet recording method describedabove. Accordingly, the recorded material can have a metallic image ofany color.

Ink Set According to Second Embodiment

An ink set according to this embodiment includes a metallic inkcomposition containing a metal pigment, a first curable ink compositioncontaining no colorant, and at least one second curable ink compositioncontaining a colorant selected from the group consisting of a chromaticpigment, a black pigment, and a white pigment. This ink set can be usedto form chromatic, black, and white images with metallic finishes.

The second embodiment is similar to the first embodiment except that theink set includes the first curable ink composition containing nocolorant and at least one second curable ink composition containing acolorant selected from the group consisting of a chromatic pigment, ablack pigment, and a white pigment, instead of at least one curable inkcomposition selected from the group consisting of a chromatic inkcomposition, a black ink composition, and a white ink composition, asused in the first embodiment. Hence, the description of the metallic inkcomposition containing the metal pigment in the first embodiment holdstrue for the second embodiment.

Next, the curable ink compositions used for the ink set according tothis embodiment will be described. The first and second curable inkcompositions used for the ink set according to this embodiment areprovided as a binary curable ink composition; the first curable inkcomposition contains no colorant, while the second photocurable inkcomposition contains a colorant selected from the group consisting of achromatic pigment, a. black pigment, and a white pigment.

Preferably, the first curable ink composition is nonaqueous and at leastcontains a photopolymerization initiator and a polymerizable compound.

Examples of the photopolymerization initiator used for the first curableink composition are similar to those shown in the first embodiment, andthe description thereof holds true for the second embodiment.

The first curable ink composition may contain two or more suchphotopolymerization initiators as described above, which may be used incombination with other photopolymerization initiators.

Examples of photopolymerization initiators that can be used incombination are similar to those shown in the first embodiment, and thedescription thereof holds true for the second embodiment.

The amount of photopolymerization initiator added is preferably 0.1% to15% by weight.

Preferably, the second curable ink composition is nonaqueous and atleast contains a polymerizable compound but contains nophotopolymerization initiator.

The polymerizable compound used for the first and second inkcompositions is preferably at least one material selected from the groupconsisting of an N-vinyl compound, ethylene glycol monoallyl ether, anda dendritic polymer in terms of storage stability.

N-vinylformamide and ethylene glycol monoallyl ether, which aremonofunctional radical polymerizable monomers, are preferred becausethey have a low tendency to undergo undesirable polymerization due todark reaction during storage.

If the amount of N-vinylformamide and/or ethylene glycol monoallyl etheradded is less than 20% by weight, the ink compositions can beunsatisfactory in terms of, for example, viscosity, dispersionstability, or storage stability. If the amount of N-vinylformamideand/or ethylene glycol monoallyl ether added is more than 80% by weight,the ink compositions can be unsatisfactory in terms of curing propertiesor coating strength as a binary curable ink composition. Morepreferably, the amount of N-vinylformamide and/or ethylene glycolmonoallyl ether added is about 20% to 70% by weight.

Examples of the dendritic polymer used in this embodiment are similar tothose shown in the first embodiment, and the description thereof holdstrue for the second embodiment.

Preferably, the dendritic polymer used in this embodiment is solid atroom temperature and has a number average molecular weight of 1,000 to100,000, particularly preferably 2,000 to 50,000. If the molecularweight falls below the above range, a printed image becomes fragile. Ifthe molecular weight exceeds the above range, the ink compositionsbecome impractical in terms of ejection properties because the inkviscosity is not sufficiently decreased by reducing the amount ofdendritic polymer added.

Other polymerizable compounds may also be contained. Examples of suchpolymerizable compounds are similar to those shown in the firstembodiment, and the description thereof holds true for the secondembodiment.

The first and second curable ink compositions may contain a surfactantsuch as a silicone surfactant. The silicone surfactant, for example, ispreferably polyester-modified silicone or polyether-modified silicone,particularly preferably polyether-modified polydimethylsiloxane orpolyester-modified polydimethylsiloxane. Examples include BYK-347,BYK-348, BYK-UV3500, BYK-UV3510, BYK-UV3530, and BYK-UV3570(manufactured by BYK-Chemie Japan K.K.).

The first and second curable ink compositions may contain apolymerization accelerator. The type and amount of polymerizationaccelerator added are as described in the first embodiment.

The first and second curable ink compositions may contain at least onethermal radical polymerization inhibitor to achieve higher storagestability. The thermal radical polymerization inhibitor used may be onecontained in a typical polymerizable composition, for example, aphenolic antioxidant, an HALS, a phosphorus antioxidant, hydroquinonemonomethyl ether, as widely used for (meth)acrylic monomers,hydroquinone, t-butylcatechol, or pyrogallol. Of these, an HALS ispreferred, as exemplified by Irgastab UV-10 (manufactured by CibaSpecialty Chemicals Inc.).

For the ink set according to this embodiment, only the second curableink composition contains a colorant. The colorant used is preferably apigment in terms of print durability. The pigment contained in thesecond curable ink composition may be at least one material selectedfrom the group consisting of a chromatic pigment, a black pigment, and awhite pigment.

An organic or inorganic pigment may be used as the pigment used for thesecond curable ink composition without any particular limitations.

Examples of the chromatic pigment, the black pigment, and the whitepigment are similar to those for the chromatic ink composition, theblack ink composition, and the white ink composition, respectively, usedin the first embodiment, and the description thereof holds true for thesecond embodiment.

The contents of the chromatic and black pigments are each preferably0.1% by weight or more, more preferably 1.0% by weight or more, stillmore preferably 3.0% to 10.0% by weight, in terms of print glossinessand a bronzing-inhibiting effect. The content of the white pigment ispreferably 1.0% by weight or more, more preferably 5.0% by weight ormore, still more preferably 10% to 20% by weight, in terms of whiteness.

In addition to the pigment used as a colorant, the second curable inkcomposition preferably contains a dispersant for dispersing the pigment.The dispersant used may be any dispersant that can be used for this typeof pigment ink, for example, a cationic dispersant, an anionicdispersant, a nonionic dispersant, or a surfactant.

Examples of the cationic dispersant, the anionic dispersant, thenonionic dispersant, and the surfactant are similar to those for thepcurable ink composition used in the first embodiment.

According to the preferred embodiment of the invention, the abovepigments can be dispersed in an aqueous medium with a dispersant or asurfactant to prepare a pigment dispersion used as the second curableink composition. The dispersant used is preferably one commonly used toprepare a pigment dispersion, for example, a polymer dispersant.

In addition to four basic colors, namely, yellow, magenta, cyan, andblack, tints and shades of the respective hues may be used as the colorof the colorant contained in the second curable ink composition used forthe ink set according to this embodiment. For example, light magenta(tint of magenta), red (shade of magenta), light cyan (tint of cyan),blue (shade of cyan), and violet can be used. In addition, neutralcolors such as green and orange can be used. As for the two achromaticcolors, namely, black and white, gray (tint of black), light black (tintof black), matt black (shade of black), cream, and ivory, for example,can be used. Furthermore, metallic colors such as silver, gold, copper,and chrome silver can be used.

Other additives may optionally be used, including a leveling agent, amatting agent, and additives for modifying the physical properties offilm, such as polyester, polyurethane, polyvinyl, acrylic resin, rubber,polyacrylic polyol, polyoxyalkylene polyalkylene amine, and wax. Inaddition, the first and second curable ink composition may contain otherknown ingredients that are commonly used for binary curable inks,including a wetting agent, a penetrant, a pH adjuster, a preservative,and a fungicide.

The ink set according to this embodiment is used by mixing the first andsecond curable ink compositions before curing them by light irradiation.The mixing, followed by the curing, may be performed before or afterprinting. That is, the mixing and the printing may be performed bydepositing the first and second curable ink compositions at the sameposition on a recording medium or by mixing the first and second curableink compositions before depositing the mixture on the recording medium.

Liquid Container and Liquid-Ejecting Apparatus

According to this embodiment, a liquid container including the ink setdescribed above can be provided. According to this embodiment,additionally, a liquid-ejecting apparatus including the liquid containercan be provided.

Ink-Jet Recording Method

An ink-jet recording method according to this embodiment for recordingby driving an ink-jet head to eject droplets of an ink composition ontoa recording medium includes forming an image using the ink set describedabove.

As in the first embodiment, the metallic ink composition containing themetal pigment can be used alone to form an image with a metallic finishwhose relative specular glossinesses at incident angles of 20°, 60°, and85°, as specified in JIS Z8741, are measured to be 200 or more, 200 ormore, and 100 or more, respectively, at the same time. The use of thismetallic ink composition allows formation of images with desiredmetallic finishes, ranging from matt images to glossy images. Examplesof images with metallic finishes that can be formed are similar to thoseof the first embodiment.

An image can be formed by simultaneously ejecting the metallic inkcomposition containing the metal pigment and the first curable inkcomposition and/or the second curable ink composition. This allows ametallic appearance to be added to the colors of the chromatic pigment,the black pigment, and the white pigment.

If the metallic ink composition containing the metal pigment and thefirst curable ink composition and/or the second curable ink compositionare separately ejected, for example, it is preferable to form an imagewith a metallic finish using the metallic ink composition containing themetal pigment before forming an image of any color by ejecting the firstcurable ink composition and/or the second curable ink composition.

The metallic pigment does not easily permeate an ink-accepting layer ona recording medium and therefore remains deposited on the recordingmedium whether it has the ink-accepting layer or not. In contrast, whenthe second curable ink composition is ejected onto the ink-acceptinglayer on the recording medium, the pigment contained therein easilypermeates the ink-accepting layer. Hence, the color of the pigment ofthe second curable ink composition can be made more distinct if themetallic ink composition containing the metal pigment is ejected ontothe recording medium to form a deposited layer of the metallic pigmentbefore the pigment contained in the second curable ink composition isdeposited thereon.

Examples of the method for ejecting the ink compositions include thefirst to fourth methods described in the first embodiment.

Any of the methods described above can be used for the ink-jet recordingmethod according to this embodiment, and the ink set according to thisembodiment can be used with an ink-jet cartridge based on any of theabove methods. To avoid heat damage to the ink compositions, the firstto third methods are preferably selected because the ink-jet head is notheated.

After the ejection of the curable ink compositions, droplets depositedon the recording medium are cured and/or dried by a common method.

An example of the method for curing includes ejecting the first curableink composition and a second curable ink composition containing thewhite pigment to form an image, curing the image by light irradiation,and ejecting (i) the metallic ink composition and (ii) the first curableink composition and/or (iii) an second photocurable ink compositioncontaining the chromatic pigment or the black pigment to form an image.

This method allows formation of a full-color image with a metallicfinish.

Another example includes ejecting the metallic ink composition to forman image, simultaneously ejecting the first curable ink compositionand/or the second curable ink composition to form an image, and curingthe image during or after the ejection.

This method allows formation of a full-color image with a metallicfinish.

The drying and the curing can also be combined by, for example, ejectingthe metallic ink composition to form an image, drying the image,simultaneously ejecting the first curable ink composition and/or thesecond curable ink composition to form an image, and curing the imageduring or after the ejection.

This method allows formation of a full-color image with a metallicfinish.

The curing is preferably performed by ultraviolet irradiation, as in thefirst embodiment, and the description thereof holds true for the secondembodiment.

Recorded Material

A recorded material according to this embodiment is obtained byrecording using the ink set and the ink-jet recording method describedabove. Accordingly, the recorded material can have a metallic image ofany color.

Example 1 1. Metallic Ink Composition (1) Preparation of MetallicPigment Dispersion

A resin-layer coating liquid containing 3.0% by weight of celluloseacetate butyrate (butylation rate: 35% to 39%; manufactured by KantoChemical Co., Inc.) and 97% by weight of diethylene glycol diethyl ether(manufactured by Nippon Nyukazai Co., Ltd.) was uniformly applied onto aPET film with a thickness of 100 μm by bar coating and was dried at 60°C. for ten minutes to form a thin resin layer on the PET film.

An aluminum layer was then deposited on the resin layer to an averagethickness of 20 nm using a vacuum deposition apparatus (VE-1010,manufactured by Vacuum Device Inc.).

The laminate thus formed was simultaneously subjected to delamination,pulverization, and dispersion in diethylene glycol diethyl ether using aultrasonic dispersion apparatus (VS-150, manufactured by AS ONECorporation) for a total ultrasonic dispersion time of 12 hours toprepare a metallic pigment dispersion.

The metallic pigment dispersion thus prepared was filtered through a 5μm mesh stainless filter to remove coarse particles. The filtrate waspoured into a round-bottom flask and was distilled using a rotaryevaporator to remove diethylene glycol diethyl ether, thus condensingthe metallic pigment dispersion. The concentration of the pigment in thecondensed metallic pigment dispersion was adjusted afterwards, so that ametallic pigment dispersion 1 having a pigment concentration of 5% byweight was obtained.

In addition, a metallic pigment dispersion 2 containing a metallicpigment was prepared under different deposition conditions and/or with adifferent ultrasonic dispersion time.

The 50% average particle sizes R50, based on a circle-equivalentdiameter in a plane including a major axis (X direction) and a minoraxis (Y direction), and the average thicknesses Z of the metallicpigments were measured using a particle size/particle distributionmeasurement apparatus (FPIA-3000S, manufactured by Sysmex Corporation),and the measurements of R50 and Z were used to calculate R50/Z. Theresults are shown in Table 1.

TABLE 1 Metallic 50% average Average pigment particle size thickness Zdispersion R50 (μm) (μm) R50/Z 1 1.03 0.02 51.5 2 1.13 0.02 56.5

(2) Preparation of Metallic Ink Composition

Metallic pigment ink compositions were prepared using the metallicpigment dispersions prepared by the method described above according tothe compositions shown in Table 2. The metallic pigment dispersions wereadded to ink solvents prepared by mixing and dissolving solvents andadditives and were mixed and stirred with a magnetic stirrer at normaltemperature and pressure for 30 minutes to prepare metallic pigment inkcompositions (S1 to S3).

In Table 2, the diethylene glycol diethyl ether (DEGdEE), dipropyleneglycol monobutyl ether (DPGmBE), and tetraethylene glycol dimethyl ether(TEGdME) used were manufactured by Nippon Nyukazai Co., Ltd. Theγ-butyrolactone used was manufactured by Kanto Chemical Co., Inc. Thepolyacrylic polyol resin emulsions (N-2043-AF-1 and N-2043-60MEX) usedwere manufactured by Harima Chemicals, Inc. The surfactant (BYK-UV3500)used was manufactured by BYK-Chemie Japan K.K. The values are expressedin percent by weight.

TABLE 2 Unit: percent by weight Metallic ink composition Ingredients S1S2 S3 DEGdEE 47.8  61.8  61.3  DPGmBE 45.0  γ-Butyrolactone 15.0  15.0 TEGdME 18.0  18.0  N-2043-AF-1 6.0 4.0 N-2043-60MEX 4.0 BYK-UV3500 0.20.2 0.2 Pigment solid 1.0 1.0 1.5 content Metallic pigment (1)   (2)  (2)   dispersion

2. Color Ink Composition (1) Preparation of Polymerizable Microparticlesand Dispersion Thereof

First, 88.1 parts by weight of a silica sol (IPA-ST, an isopropylalcohol (hereinafter referred to as “IPA”) dispersion containing 30% byweight of silica, manufactured by Nippon Chemical Industrial Co., Ltd.)was poured into a 200 ml Erlenmeyer flask, to which 7.9 parts by weightof 3-methacryloxypropyltrimethoxysilane (silane coupling agent SILA-ACES710, manufactured by Chisso Corporation) was added. Then, 4 parts byweight of 0.05 mol/L hydrochloric acid was added to the dispersion withstirring using a magnetic stirrer. The dispersion was stirred at roomtemperature for 24 hours to facilitate its reaction, thus preparing anIPA dispersion A containing polymerizable microparticles (MPS) havingmethacryloyl groups.

In addition, a dispersion B containing 30% by weight of thepolymerizable microparticles was prepared by pouring 70 parts by weightof N-vinylformamide (hereinafter referred to as “NVF”) (Beamset 770,manufactured by Arakawa Chemical Industries, Ltd.) and 100 parts byweight of the above dispersion A into a 300 ml round-bottom flask andremoving IPA using a rotary evaporator.

(2) Preparation of Pigment Dispersion (2-1) Yellow Pigment Dispersion(C)

As a pigment used as a colorant, C.I. Pigment Yellow (P.Y.) 74,polyurethane (average molecular weight: about 20,000; hereinafterreferred to as a “dispersant”), and NVF were mixed in a ratio of 15:5:80and were subjected to dispersion in a sand mill (manufactured byYasukawa Seisakusho) with glass beads (diameter: 1.7 mm) weighing 1.5times the weight of the mixture for two hours. The glass beads wereremoved afterwards, thus obtaining a pigment dispersion C (pigmentconcentration: 15% by weight).

(2-2) Magenta Pigment Dispersion (D)

A pigment dispersion D (pigment concentration: 15% by weight) wasprepared in the same manner as the pigment dispersion C except that thepigment used was C.I. Pigment Red (P.R.) 122.

(2-3) Cyan Pigment Dispersion (E)

A pigment dispersion E (pigment concentration: 15% by weight) wasprepared in the same manner as the pigment dispersion C except that thepigment used was C.I. Pigment Blue (P.B.) 15:3.

(2-4) Black Pigment Dispersion (F)

A pigment dispersion F (pigment concentration: 15% by weight) wasprepared in the same manner as the pigment dispersion C except that thepigment used was C.I. Pigment Black (P.Bk.) 7.

(2-5) White Pigment Dispersion (G)

A titanium-bearing ore was dissolved in sulfuric acid to prepare atitanium sulfate solution. The titanium sulfate solution was subjectedto hydrolysis to obtain hydrous titanium oxide. Added to 100 parts byweight of the hydrous titanium oxide in terms of titanium dioxidecontent were 0.50 parts by weight of ammonium phosphate, 0.30 parts byweight of potassium sulfate, and 0.30 parts by weight of aluminumsulfate. The hydrous titanium oxide was heated in a rotary mufflefurnace for laboratory use until the product temperature reached 1,020°C., thus obtaining titanium dioxide microparticles. The microparticleswere cooled to room temperature and were examined by transmissionelectron microscopy, revealing that the microparticles were anatasemicroparticles with an average primary particle size of 0.13 μm.

Then, 15 parts by weight of the titanium dioxide microparticles, servingas a surface-finished white pigment, 5 parts by weight of apolyoxyalkylene-added polyalkylene amine (Discole N-518, manufactured byDai-ich Kogyo Seiyaku Co., Ltd.), serving as a dispersant, and 80 partsby weight of ethylene glycol monoallyl ether (hereinafter referred to as“AG”) were mixed and were subjected to dispersion in a sand mill(manufactured by Yasukawa Seisakusho) with zirconia beads (diameter: 1.0mm) weighing 1.5 times the weight of the slurry for two hours. The beadswere removed afterwards, thus obtaining a pigment dispersion Gcontaining 60% by weight of the titanium dioxide microparticles.

(3) Preparation of Ink Composition (3-1) Yellow Pigment Ink Composition(Y1)

First, 20 parts by weight of the dispersion B and 10 parts by weight ofthe pigment dispersion C were poured into a light-tight container. Addedto the dispersion were 29 parts by weight of NVF, 25 parts by weight oftripropylene glycol diacrylate (hereinafter referred to as “TPGDA”;Aronix M-220, manufactured by Toagosei Co., Ltd.), 10 parts by weight ofethylene oxide-modified glycerol triacrylate (hereinafter referred to as“AGE3”, HK Ester A-Gly-3E, manufactured by Shin-Nakamura Chemical Co.,Ltd.), 4.0 parts by weight of bis(2,4,6-trimethylbenzoyl)phenylphosphineoxide (Irgacure 819, manufactured by Ciba Specialty Chemicals Inc.), 1.0part by weight of2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1 (Irgacure 369,manufactured by Ciba Specialty Chemicals Inc.), and 1 part by weight of2-ethylhexyl 4-dimethylaminobenzoate (Darocur EHA, manufactured by CibaSpecialty Chemicals Inc.). The dispersion was mixed and stirred with amagnetic stirrer for one hour and was filtered through a 5 μm meshmembrane filter in an ultraviolet-shielded environment to prepare ayellow ink composition Y1 having the composition shown in Table 3.

(3-2) Magenta, Cyan, and Black Pigment Ink Compositions (M1, C1, andBk1)

Similarly, a magenta ink composition M1, a cyan ink composition C1, anda black ink composition Bk1 having the compositions shown in Table 3were prepared using the pigment dispersions D, E, and F, respectively,instead of the pigment dispersion C.

TABLE 3 Unit: percent by weight Ingredients Y1 M1 C1 Bk1 NVF 51.0 51.051.0 51.0 TPGDA 25.0 25.0 25.0 25.0 AGE3 10.0 10.0 10.0 10.0 Dispersant0.5 0.5 0.5 0.5 Irgacure 819 4.0 4.0 4.0 4.0 Irgacure 369 1.0 1.0 1.01.0 Darocur EHA 1.0 1.0 1.0 1.0 Polymerizable 6.0 6.0 6.0 6.0microparticles Colorant PY 74 PR 122 PB 15:3 PBk 7 1.5 1.5 1.5 1.5

(3-3) White Ink Composition (W1)

Of the ingredients shown in Table 4, the solvents and additives otherthan AG, the pigment, and the dispersant were mixed and completelydissolved to prepare an ink solvent. The pigment dispersion G wasgradually dripped into the ink solvent with stirring. After the drippingwas completed, the mixture was stirred at room temperature for 30minutes and was filtered through a 5 μm membrane filter to prepare awhite ink composition W1 shown in Table 4. In the composition shown inTable 4, “AG” refers to ethylene glycol monoallyl ether manufactured byNippon Nyukazai Co., Ltd., “Irgacure 127” refers to a polymerizationinitiator manufactured by Ciba Specialty Chemicals Inc., “Darocur EDB”refers to a polymerization accelerator manufactured by Ciba SpecialtyChemicals Inc., “BYK-UV3570” refers to a silicone surfactantmanufactured by BYK-Chemie Japan K.K., and “Irgastab UV-10” refers to apolymerization inhibitor manufactured by Ciba Specialty Chemicals Inc.

TABLE 4 Unit: percent by weight Ingredients W1 NVF 25.0 AG 47.6Hyperbranched polymer 10.0 Polyoxyalkylene-added 2.0 polyalkylene amineIrgacure 819 6.4 Irgacure 127 1.6 Darocur EDB 1.0 BYK-UV3570 0.2Irgastab UV10 0.2 Titanium dioxide 6.0 microparticles

(3-4) Yellow, Magenta, Cyan, Black, and White Pigment Ink Compositions(Y2, M2, C2, Bk2, and W2)

Similarly, a yellow ink composition Y2, a magenta ink composition M2, acyan ink composition C2, a black ink composition Bk2, and a white inkcomposition W2 having the compositions shown in Table 5 were prepared.

TABLE 5 Unit: percent by weight Ingredients Y2 M2 C2 Bk2 W2 NVF 25.025.0 25.0 25.0 — AG 41.6 41.6 41.6 41.6 57.6 Viscoat #1000 20.0 20.022.5 22.5 25.0 Irgacure 819 4.0 4.0 4.0 4.0 4.0 Irgacure 127 1.0 1.0 1.01.0 1.0 BYK-UV3500 0.2 0.2 0.2 0.2 0.2 Irgastab UV10 0.2 0.2 0.2 0.2 0.2Dispersant 2.0 2.0 1.5 1.5 4.0 Colorant PY 213 PV 19 PB 15:3 PBk 7Titanium dioxide microparticles 6.0 6.0 4.0 4.0 8.0

3. Ink Set

The ink compositions prepared in Items 1 and 2 above were used to formink sets having the combinations shown in Table 6.

TABLE 6 Metallic ink Chromatic ink Black ink White ink Ink set A S1 C1,M1, Y1 Bk1 W1 Ink set B S2 C1, M1, Y1 Bk1 W1 Ink set C S3 C1, M1, Y1 Bk1W1 Ink set D S1 C2, M2, Y2 Bk2 W2 Ink set E S2 C2, M2, Y2 Bk2 W2 Ink setF S3 C2, M2, Y2 Bk2 W2

4. Print Evaluation Test

The ink sets of Item 3 above were used with an ink-jet printer (SJ-540,manufactured by Roland DG Corporation). The ink compositions werecharged into the corresponding color lines. That is, the black, yellow,magenta, and cyan ink compositions were charged into black, yellow,magenta, and cyan lines, respectively. The metallic and white inkcompositions were charged into light cyan and light magenta lines,respectively. Printing was performed according to the print patternsdescribed below. The recording media used were A4-size poly(vinylchloride) sheets (Viewcal 2000 (white), manufactured by Sakurai Co.,Ltd.), A4-size PET films (PG-50L, manufactured by Rami CorporationInc.), and A4-size polycarbonate films (Iupilon FE-2000, manufactured byMitsubishi Engineering-Plastics Corporation). Printouts were evaluatedaccording to the following evaluation criteria. The results are shown inTable 7.

AA: A metallic finish on which a reflection of an object could beclearly seen was formed.

A: A metallic finish on which a reflection of an object could beslightly seen was formed.

B: A matt metallic finish was formed.

C: No metallic finish was formed.

The print patterns using the above ink sets were as follows.

a. Print Pattern 1

A metallic image was formed using the metallic ink composition at aheating temperature of 50° C., and an image was further formed on themetallic image using the chromatic ink compositions. The image was thenirradiated with ultraviolet light using an ultraviolet irradiationapparatus including an ultraviolet light-emitting diode having a peakwavelength of 365 nm (NICHIA i-LED NCCUO33, manufactured by NichiaCorporation), an ultraviolet light-emitting diode having a peakwavelength of 380 nm (NICHIA NCCU001, manufactured by NichiaCorporation), and a light-emitting diode having a peak wavelength of 395nm (E1S40-0POC6-01, manufactured by Toyoda Gosei Co., Ltd.). Theintensity of ultraviolet irradiation on a surface under irradiation was20 mW/cm² for each of the diodes having peak wavelengths of 365, 380,and 395 nm, that is, a total of 60 mW/cm². The ultraviolet irradiationwas performed for five seconds under such conditions that the totalquantity of light per ultraviolet irradiation was 300 mJ/cm², thuscuring the image.

b. Print Pattern 2

An image was formed by ejecting the metallic ink composition at aheating temperature of 50° C., and an image was further formed using thechromatic ink compositions. The image was then irradiated withultraviolet light using an ultraviolet irradiation apparatus includingan ultraviolet light-emitting diode having a peak wavelength of 365 nm(NICHIA i-LED NCCUO33, manufactured by Nichia Corporation), anultraviolet light-emitting diode having a peak wavelength of 380 nm(NICHIA NCCU001, manufactured by Nichia Corporation), and alight-emitting diode having a peak wavelength of 395 nm (E1S40-0P0C6-01,manufactured by Toyoda Gosei Co., Ltd.). The intensity of ultravioletirradiation on a surface under irradiation was 20 mW/cm² for each of thediodes having peak wavelengths of 365, 380, and 395 nm, that is, a totalof 60 mW/cm². The ultraviolet irradiation was performed for five secondsunder such conditions that the total quantity of light per ultravioletirradiation was 300 mJ/cm², thus curing the image. An image was furtherformed by simultaneously ejecting the black ink composition and thewhite ink composition and was cured during or after the ejection byultraviolet irradiation under the same conditions as above.

c. Print Pattern 3

An image was formed using the metallic ink composition at a heatingtemperature of 50° C., and an image was further formed by ejecting thechromatic ink compositions, the black ink composition, and the white inkcomposition. The image was then irradiated with ultraviolet light usingan ultraviolet irradiation apparatus including an ultravioletlight-emitting diode having a peak wavelength of 365 nm (NICHIA i-LEDNCCUO33, manufactured by Nichia Corporation), an ultravioletlight-emitting diode having a peak wavelength of 380 nm (NICHIA NCCU001,manufactured by Nichia Corporation), and a light-emitting diode having apeak wavelength of 395 nm (E1S40-0P0C6-01, manufactured by Toyoda GoseiCo., Ltd.). The intensity of ultraviolet irradiation on a surface underirradiation was 20 mW/cm² for each of the diodes having peak wavelengthsof 365, 380, and 395 nm, that is, a total of 60 mW/cm². The ultravioletirradiation was performed for five seconds under such conditions thatthe total quantity of light per ultraviolet irradiation was 300 mJ/cm²,thus curing the image.

d. Print Pattern 4

An image was formed using the metallic ink composition at a heatingtemperature of 50° C. and was dried at 60° C. for 15 minutes, and animage was further formed by ejecting the chromatic ink compositions, theblack ink composition, and the white ink composition. The image was thenirradiated with ultraviolet light using an ultraviolet irradiationapparatus including an ultraviolet light-emitting diode having a peakwavelength of 365 nm (NICHIA i-LED NCCUO33, manufactured by NichiaCorporation), an ultraviolet light-emitting diode having a peakwavelength of 380 nm (NICHIA NCCU001, manufactured by NichiaCorporation), and a light-emitting diode having a peak wavelength of 395nm (E1S40-0P0C6-01, manufactured by Toyoda Gosei Co., Ltd.). Theintensity of ultraviolet irradiation on a surface under irradiation was20 mW/cm² for each of the diodes having peak wavelengths of 365, 380,and 395 nm, that is, a total of 60 mW/cm². The ultraviolet irradiationwas performed for five seconds under such conditions that the totalquantity of light per ultraviolet irradiation was 300 mJ/cm², thuscuring the image.

TABLE 7 Print pattern 1 2 3 4 Ink set A B B B A Ink set B A A A AA Inkset C AA AA AA AA Ink set D B B B A Ink set E A A A AA Ink set F AA AAAA AA

As shown in Table 7, recorded materials with metallic images of anycolors could be obtained using the ink sets and the ink-jet recordingmethods described above.

Example 2 1. Metallic Ink Composition

The metallic ink compositions S1 to S3 prepared in the same manner as inExample 1 were used.

2. Color Ink Composition (1) Preparation of Dendritic Polymer

A hyperbranched polymer and dendrimers were used as dendritic polymersin this example.

The hyperbranched polymer used was “STAR-501”, manufactured by OsakaOrganic Chemical Industry Ltd. “STAR-501”, a hyperbranched polymerhaving a dipentaerythritol core with branches of functional groups,contained dipentaerythritol hexaacrylate as a diluent monomer and had aviscosity of 210 mPa·s and 20 to 99 functional groups (acrylic groups).

Dendrimers 7 and 9 were synthesized as follows.

First, 31 g of ethylenediamine, 256 g of dimethyl acrylate, and 300 g ofmethanol were poured into a 1′L reaction container and were allowed toreact with stirring at 40° C. in a nitrogen gas flow for six hours.After the reaction was completed, the mixture was distilled using arotary evaporator to remove methanol and was purified by reprecipitationin an excess of diethyl ether. A resultant reaction product 1 wasdissolved in 500 g of methanol before the subsequent reaction.

The methanol solution containing the reaction product 1 was poured intoa 2 L reaction container, was mixed with 240 g of ethylenediamine, andwas allowed to react with stirring at 27° C. in a nitrogen gas flow forsix hours. After the reaction, the methanol removal and the purificationby reprecipitation were similarly performed. A resultant reactionproduct 2 was dissolved in 1,000 g of methanol before the subsequentreaction.

The methanol solution containing the reaction product 2 was poured intoa 5 L reaction container, was mixed with 667 g of dimethyl acrylate, andwas allowed to react with stirring at 40° C. in a nitrogen gas flow forsix hours. After the reaction, the methanol removal and the purificationby reprecipitation were similarly performed. A resultant reactionproduct 3 was dissolved in 2,000 g of methanol before the subsequentreaction.

The methanol solution containing the reaction product 3 was poured intoa reaction container, was mixed with 361 g of ethylenediamine, and wasallowed to react with stirring at 27° C. in a nitrogen gas flow for sixhours. After the reaction, the methanol removal and the purification byreprecipitation were similarly performed. A resultant reaction product 4was dissolved in 2,000 g of acetone dehydrated through a molecular sievebefore the subsequent reaction.

Poured into a reaction container were 1,000 g of the acetone solutioncontaining the reaction product 4 and 2,153 g of1,1-bis(acryloyloxymethyl)ethyl isocyanate (Karenz BEI, manufactured byShowa Denko K.K.), which were mixed and stirred in a nitrogen gas flow,were mixed and stirred with 1 g of 1,4-diazabicyclo[2.2.2]octane (DABCO,manufactured by Tokyo Chemical Industry Co., Ltd.), and were allowed toreact for six hours after the reaction temperature was raised to 50° C.

After the reaction was completed, the mixture was distilled using arotary evaporator to remove acetone and was mixed with 6,838 g ofethylene glycol monoallyl ether to prepare an ethylene glycol monoallylether solution 8 containing 30% by weight of the dendrimer 7. Eachmolecule of the dendrimer 7 had 72 acryloyl groups attached to theoutermost side thereof.

Also, the acetone solution containing the reaction product 4 wasdistilled using a rotary evaporator to remove acetone and was mixed with6,838 g of ethylene glycol monoallyl ether to prepare an ethylene glycolmonoallyl ether solution 10 containing 30% by weight of the dendrimer 9.Each molecule of the dendrimer 9 molecules had no radical polymerizablegroups attached to the outermost side thereof.

(2) Preparation of Pigment Dispersion

Pigment dispersions were prepared by the following method. First, 15parts by weight of C.I. Pigment Black 7 (carbon black), serving as acolorant, and 3.5 parts by weight of Discole N-509 (manufactured byDainichiseika Color & Chemicals Mfg. Co., Ltd.), serving as adispersant, were mixed and stirred with ethylene glycol monoallyl ether(hereinafter referred to as “AG”; manufactured by Nippon Nyukazai Co.,Ltd.), serving as a monomer, so that the total amount of the mixture was100 parts by weight. The mixture was subjected to dispersion in a sandmill (manufactured by Yasukawa Seisakusho) with zirconia beads(diameter: 1.5 mm) for six hours. The zirconia beads were removed usinga separator afterwards, thus obtaining a black pigment dispersion.

Similarly, pigment dispersions corresponding to the respective colors,that is, a cyan pigment dispersion (C.I. Pigment Blue 15:3), a magentapigment dispersion (C.I. Pigment Violet 19), a yellow pigment dispersion(C.I. Pigment Yellow 155), and a white pigment dispersion (titaniumdioxide microparticles) were prepared.

(3) Preparation of Ink Compositions A1 and B1 to B5

Ink compositions A1 and B1 to B5 were prepared according to thecompositions shown in Table 8. Specifically, the monomer, radicalphotopolymerization initiator, polymerization accelerator, surfactant,and thermal radical polymerization inhibitor shown in Table 8 were mixedand completely dissolved. In preparation of the ink compositionscontaining the pigment dispersions, the pigment dispersions weregradually dripped into the solvent with stirring. After the dripping wascompleted, the mixtures were stirred at room temperature for one hourand were filtered through a 5 μm membrane filter, thus obtaining atransparent ink composition (ink composition A1), a black inkcomposition (ink composition B1), a yellow ink composition (inkcomposition B2), a magenta ink composition (ink composition B3), a cyanink composition (ink composition B4), and a white ink composition (inkcomposition B5). The values in Table 8 are expressed in percent byweight.

In Table 8, “NVF” refers to N-vinylformamide manufactured by ArakawaChemical Industries, Ltd., “AG” refers to ethylene glycol monoallylether manufactured by Nippon Nyukazai Co., Ltd., “STAR-501” refers to ahyperbranched polymer manufactured by Osaka Organic Chemical IndustryLtd., “Irgacure 819” and “Irgacure 127” refer to radicalphotopolymerization initiators manufactured by Ciba Specialty ChemicalsInc., “Darocur EHA” refers to a polymerization accelerator manufacturedby Ciba Specialty Chemicals Inc., “BYK-UV3570” refers to a siliconesurfactant manufactured by BYK-Chemie Japan K.K., and “Irgastab UV-10”refers to a thermal radical polymerization inhibitor manufactured byCiba Specialty Chemicals Inc.

TABLE 8 Unit: percent by weight Ink Composition Ingredients A1 B1 B2 B3B4 B5 NVF 25.0 25.0 25.0 25.0 25.0 25.0 AG 59.3 57.7 57.7 57.7 57.7 57.7STAR-501 6.6 13.2 13.2 13.2 13.2 13.2 Irgacure 819 6.4 — — — — —Irgacure 127 1.6 — — — — — Darocur EHA 1.0 1.0 1.0 1.0 1.0 1.0BYK-UV3570 0.1 0.1 0.1 0.1 0.1 0.1 Irgastab UV10 0.05 0.05 0.05 0.050.05 0.05 Pigment — PBk 7 PY 151 PV 19 PB 15:3 PW 6 Pigment solid — 3.03.0 3.0 3.0 3.0 content

(4) Preparation of Ink Compositions A2 and B6 to B10

Similarly, a transparent ink composition (ink composition A2), a blackink composition (ink composition B6), a yellow ink composition (inkcomposition B7), a magenta ink composition (ink composition B8), a cyanink composition (ink composition B9), and a white ink composition (inkcomposition B10) were prepared according to the compositions shown inTable 9. The values in Table 9 are expressed in percent by weight.

In Table 9, “Viscoat #1000” refers to a hyperbranched polymermanufactured by Osaka Organic Chemical Industry Ltd.

TABLE 9 Unit: percent by weight Ink Composition Ingredients A2 B6 B7 B8B9 B10 NVF 25.0 25.0 25.0 25.0 25.0 25.0 AG 54.6 51.6 51.6 51.6 51.648.6 Viscoat #1000 15.0 20.0 20.0 20.0 20.0 20.0 Irgacure 819 4.0 — — —— — Irgacure 127 1.0 — — — — — BYK-UV3500 0.2 0.2 0.2 0.2 0.2 0.2Irgastab UV10 0.2 0.2 0.2 0.2 0.2 0.2 Pigment — PBk 7 PY 213 PV 19 PB15:3 PW 6 Pigment solid — 3.0 3.0 3.0 3.0 6.0 content

3. Ink Set

The ink compositions prepared in Items 1 and 2 above were used to formink sets having the combinations shown in Table 10.

TABLE 10 Metallic ink Transparent ink Color ink Ink set G S1 A1 B1-B5 Ink set H S2 A1 B1-B5  Ink set I S3 A1 B1-B5  Ink set J S1 A2 B6-B10 Inkset K S2 A2 B6-B10 Ink set L S3 A2 B6-B10

4. Print Evaluation Test

The ink sets of Item 3 above were used with two ink-jet printers(SJ-540, manufactured by Roland DG Corporation). For one of the twoink-jet printers (IJP-1), the ink compositions S1 to S3 (metallic inkcompositions), the ink compositions A1 and A2 (transparent inkcompositions), and the ink compositions B5 and B10 (white inkcompositions) were charged into a black line, a light cyan line, and alight magenta line, respectively.

For the other ink-jet printer (IJP-2), the ink compositions B1 and B6(black ink compositions), the ink compositions B2 and B7 (yellow inkcompositions), the ink compositions B3 and B8 (magenta inkcompositions), and the ink compositions B4 and B9 (cyan inkcompositions) were charged into a black line, a yellow line, a magentaline, and a cyan line, respectively, and the ink compositions A1 and A2(transparent ink compositions) and the ink compositions B5 and B10(white ink compositions) were charged into a light cyan line and a lightmagenta line, respectively. Printing was performed according to theprint patterns described below.

The recording media used were A4-size poly(vinyl chloride) sheets(Viewcal 2000 (white), manufactured by Sakurai Co., Ltd.), A4-size PETfilms (PG-50L, manufactured by Rami Corporation Inc.), and A4-sizepolycarbonate films (Iupilon FE-2000, manufactured by MitsubishiEngineering-Plastics Corporation). Printouts were evaluated according tothe following evaluation criteria. The results are shown in Table 11.

AA: A metallic finish on which a reflection of an object could beclearly seen was formed.

A: A metallic finish on which a reflection of an object could beslightly seen was formed.

B: A matt metallic finish was formed.

C: No metallic finish was formed.

The print patterns using the above ink sets were as follows.

a. Print Pattern 1

Using the IJP-1, an image was formed by simultaneously ejecting themetallic ink composition S1, the ink composition A1 or A2 (transparentink composition), and the ink composition B5 or B10 (white inkcomposition) under such heating conditions that the surface temperatureof a recording medium reached 50° C. The image was then cured byultraviolet irradiation using an ultraviolet irradiation apparatus.

The ultraviolet irradiation apparatus included an ultravioletlight-emitting diode having a peak wavelength of 365 nm (NICHIA i-LEDNCCUO33, manufactured by Nichia Corporation), an ultravioletlight-emitting diode having a peak wavelength of 380 nm (NICHIA NCCU001,manufactured by Nichia Corporation), and a light-emitting diode having apeak wavelength of 395 nm (E1S40-0POC6-01, manufactured by Toyoda GoseiCo., Ltd.).

The intensity of ultraviolet irradiation on a surface under irradiationwas 20 mW/cm² for each of the diodes having peak wavelengths of 365,380, and 395 nm, that is, a total of 60 mW/cm². The ultravioletirradiation was performed for five seconds under such conditions thatthe total quantity of light per ultraviolet irradiation was 300 mJ/cm².

b. Print Pattern 2

Using the IJP-1, an image was formed using the metallic ink compositionS1 under such heating conditions that the surface temperature of arecording medium reached 50° C. Using the IJP-2, subsequently, an imagewas further formed on the image by simultaneously ejecting the inkcomposition A1 or A2 (transparent ink composition) and the inkcompositions B1 to B5 or B6 to B10 (black, yellow, magenta, cyan, andwhite ink compositions). The image was then cured by ultravioletirradiation under the same conditions as the print pattern 1.

c. Print Pattern 3 Using the IJP-1, a white image was formed on arecording medium by simultaneously ejecting the ink composition A1 or A2(transparent ink composition) and the ink composition B5 or B10 (whiteink composition). The image was then cured by ultraviolet irradiationunder the same conditions as the print pattern 1.

Using the IJP-1, subsequently, a metallic image was formed using themetallic ink composition S1 under such heating conditions that thesurface temperature of the recording medium reached 50° C. Using theIJP-2, an image was further formed on the metallic image bysimultaneously ejecting the ink composition A1 or A2 (transparent inkcomposition) and the ink compositions B1 to B5 or B6 to B10 (black,yellow, magenta, cyan, and white ink compositions). The image was thencured by ultraviolet irradiation under the same irradiation conditionsas above.

The print evaluation was also performed using the same print patterns 1to 3 by replacing the metallic ink composition S1 with the metallic inkcompositions S2 and S3.

TABLE 11 Print pattern 1 2 3 Ink set G A A B Ink set H AA AA B Ink set IAA AA B Ink set J A A B Ink set K AA AA B Ink set L AA AA B

As shown in Table 11, recorded materials with metallic images of anycolors could be obtained using the ink sets and the ink-jet recordingmethods described above.

1-11. (canceled)
 12. An ink-jet recording method for forming an imageonto a recording medium comprising: ejecting a metallic nonaqueous inkcomposition containing a metal pigment and an organic solvent being amixture of at least one of an alkylene glycol ether and a lactone, thelactone comprising at least one of γ-butyrolactone, σ-valerolactone, andε-caprolactone, wherein the metal pigment includes flat particles havingthe 50% average particle size R50 of 0.5 to 3 μm, based on thecircle-equivalent diameter determined from the area of the flatparticles in the X-Y plane, wherein X is the major axis of the flatparticles in the plane and Y is the minor axis of the flat particles inthe plane, the flat particles satisfying the condition R50/Z>5, whereinZ is the thickness of the flat particles onto the recording medium toform an image with a metallic finish on a recording medium and ejectingat least one ink composition selected from the group consisting of achromatic ink composition, a black ink composition and a white inkcomposition onto the image with a metallic finish to form an image ofany color with a metallic finish.
 13. The ink-jet recording methodaccording to claim 12, wherein the image formation includessimultaneously ejecting the metallic ink composition and the curable inkcomposition selected from the group consisting of the chromatic inkcomposition, the black ink composition, and the white ink composition toform an image of any color.
 14. The ink-jet recording method accordingto claim 12, wherein the image formation includes ejecting the metallicink composition to form an image, ejecting the chromatic ink compositionto form an image of any color, ejecting the black ink composition and/orthe white ink composition, and curing the image during or after theejection.
 15. The ink-jet recording method according to claim 12,wherein the image formation includes ejecting the metallic inkcomposition to form an image, simultaneously ejecting the chromatic inkcomposition, the black ink composition, and the white ink composition,and curing the image during or after the ejection.
 16. The ink-jetrecording method according to claim 12, wherein the image formationincludes ejecting the metallic ink composition to form an image, dryingthe image, ejecting the chromatic ink composition, the black inkcomposition, and the white ink composition to form an image of anycolor, and curing the image.
 17. The ink-jet recording method accordingto claim 15, wherein the curing is performed by ultraviolet irradiation.18. The method of claim 12, wherein the organic solvent comprises analkylene glycol diether and an alkylene glycol monoether.
 19. The methodof claim 12, wherein the alkylene glycol monoethers comprises one ormore of ethylene glycol monomethyl ether, ethylene glycol monoethylether, ethylene glycol monoisopropyl ether, ethylene glycol monobutylether, ethylene glycol monohexyl ether, ethylene glycol monophenylether, diethylene glycol monomethyl ether, diethylene glycol monoethylether, diethylene glycol monobutyl ether, diethylene glycol dimethylether, diethylene glycol diethyl ether, triethylene glycol monomethylether, triethylene glycol monoethyl ether, triethylene glycol monobutylether, tetraethylene glycol monomethyl ether, tetraethylene glycolmonoethyl ether, propylene glycol monomethyl ether, propylene glycolmonoethyl ether, dipropylene glycol monomethyl ether, and dipropyleneglycol monoethyl ether, and the alkylene glycol diethers comprises oneor more of ethylene glycol dimethyl ether, ethylene glycol diethylether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether,diethylene glycol diethyl ether, diethylene glycol dibutyl ether,triethylene glycol dimethyl ether, triethylene glycol diethyl ether,triethylene glycol dibutyl ether, tetraethylene glycol dimethyl ether,tetraethylene glycol diethyl ether, tetraethylene glycol dibutyl ether,propylene glycol dimethyl ether, propylene glycol diethyl ether,dipropylene glycol dimethyl ether, and dipropylene glycol diethyl ether.20. The method of claim 12, wherein the image with a metallic finishexhibits a relative specular glossinesses at incident angles of 20°,60°, and 85°, as specified in Japanese Industrial Standards (JIS) Z8741,that are measured to be 200 or more and less than 400, 200 or more andless than 400, and 100 or more, respectively.
 21. The method of claim12, wherein the image with a metallic finish exhibits a relativespecular glossinesses at incident angles of 20°, 60°, and 85°, asspecified in Japanese Industrial Standards (JIS) Z8741, that aremeasured to be 400 or more and less than 600, 400 or more and less than600, and 100 or more, respectively.
 22. The method of claim 12, furthercomprising ejecting the white ink composition, and a least one of thechromatic in composition and the black ink composition.